String gas cosmology and structure formation

@article{Brandenberger2007StringGC,
  title={String gas cosmology and structure formation},
  author={R. Brandenberger and A. Nayeri and S. Patil and C. Vafa},
  journal={International Journal of Modern Physics A},
  year={2007},
  volume={22},
  pages={3621-3642}
}
It has recently been shown that a Hagedorn phase of string gas cosmology may provide a causal mechanism for generating a nearly scale-invariant spectrum of scalar metric fluctuations, without the need for an intervening period of de Sitter expansion. A distinctive signature of this structure formation scenario would be a slight blue tilt of the spectrum of gravitational waves. In this paper we give more details of the computations leading to these results, and the assumptions underlying them. 

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